$(document).ready(function(){
    // if the function argument is given to overlay,
    // it is assumed to be the onBeforeLoad event listener
    $("a[rel]").overlay({
        mask: '#666',
        effect: 'apple',
        fixed:false,
        onBeforeLoad: function() {

            // grab wrapper element inside content
            var wrap = this.getOverlay().find(".contentWrap");

            // load the page specified in the trigger
            wrap.load(this.getTrigger().attr("href"));
        }
    });
});